Urgently need help with alebra problem!!

Hi
My 15 year old daughter urgently needs help with two algebra problems for her year 10 maths. We would be very grateful if someone could show us how to solve the following two problems.

1)
A school is expected to plant trees along a river bank. The project is to take a certain number of days.
If they plant 240 trees per day, then they will be short by 400 trees.
If they plant 280 trees per day, they will plant 200 more than planned.
How many trees are planted, and how many days will it take?
2)A train passes a pole in 15 seconds, and in 45 seconds it passes through a tunnel 600 metres long. What is the speed of the train? How long is it?